THE PHOTOGRAPHY OF FISH. 71 



their broad heads, The arrangement is the same both 

 sides. If we now take two pieces of plate glass and 

 clamp them in close contact with the indiarubber, a 

 pad being placed between clamp and glass to avoid 

 fracture, we shall find a very simple and efficient water- 

 holding tank. In the figure III represents the india- 

 rubber tubing, G the glass, and C the clamps, the pads 

 being omitted for the sake of clearness. The writer has 

 found ordinary fretwork clamps, with pads formed of 

 thin strips of wood, answer admirably. The great 

 advantage in the employment of a tank ot this kind is 

 that it can be used " dry " for the photography of 

 insects, reptiles, and small mammalia, and, as it has a 

 flat bottom, can have any kind of groundwork inserted 

 which is suitable to the subject. Moreover, it can be 

 taken to pieces and cleaned in a few minutes. For use 

 as a dry tank one clamp at each side will be found 

 sufficient. A lid, of course, is necessary, and nothing 

 is better than a strip of perforated zinc. If thicker 

 plate glass and gas-tubing are employed it will be 

 found that a tank can be constructed capable of holding 

 practically anything that is not large enough to admit 

 of treatment with a hand-camera 



To deal with fish-photography satisfactorily it is 

 obvious that in addition to the arrangements described 

 above one must have some convenient method of 

 photographing vertically. This is absolutely essential 

 in the case of flat fish, and highly desirable in the case 

 of eels, bullheads, and ground feeders in general. Mr. 

 Saville-Kent, in his " Great Barrier Reef of Australia," 



